Nanoparticles are particles having a particle size of the nanoscale, and show optical, electrical and magnetic properties completely different from those of bulk materials due to a large specific surface area and the quantum confinement effect, in which energy required for electron transfer changes depending on the size of material. Accordingly, due to such properties, much interest has been concentrated on their applicability in the catalytic, electromagnetic, optical, medical fields, and the like. The nanoparticles may be referred to as intermediates between bulks and molecules, and may be synthesized in terms of an approach in two directions, that is, the “top-down” approach and the “bottom-up” approach.
Examples of a method for synthesizing a metal nanoparticle include a method for reducing metal ions in a solution by using a reducing agent, a method for synthesizing a metal nanoparticle using gamma-rays, an electrochemical method, and the like, but in the existing methods, it is difficult to synthesize nanoparticles having a uniform size and shape, or it is difficult to economically mass-produce high-quality nanoparticles for various reasons such as problems of environmental contamination, high costs, and the like by using organic solvents.
Further, since the metal nanoparticles become easily unstable by heat treatment temperature and the reaction temperature, there are many cases where the metal nanoparticles are dispersed in a carrier and used. Therefore, there is a need for developing a method which may efficiently support metal nanoparticles on a carrier.